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                                                                  EXHIBIT 10.43

                             SUPPLEMENTAL INDENTURE


         SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"), dated as of
March 11, 1999 among HS RESOURCES, INC., a Delaware corporation (the "Company"),
and HARRIS TRUST AND SAVINGS BANK, an Illinois banking corporation, as trustee
under the Indenture referred to below (the "Trustee").

                              W I T N E S S E T H :


         WHEREAS, the Company has heretofore executed and delivered to the
Trustee an Indenture (as amended from time to time, the "Indenture"), dated as
of December 1, 1993, providing for the issuance of $75,000,000 aggregate
principal amount of 9-7/8% Senior Subordinated Notes due 2003;


         WHEREAS, effective December 31, 1998, the Company changed its method of
accounting from the full cost method to the successful efforts method. Two
changes to the Indenture need to be made in order that the Indenture operate
materially as originally intended under the Company's new method of accounting.


         WHEREAS, pursuant to Section 9.1 of the Indenture, the Trustee and the
Company are authorized to execute and deliver this Supplemental Indenture;


         NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, the Company
and the Trustee mutually covenant and agree for the equal and ratable benefit of
the holders of the Securities as follows:


         1.       Definitions.


                   (a) Capitalized terms used herein without definition shall
have the meanings assigned to them in the Indenture.


                   (b) For all purposes of this Supplemental Indenture, except
as otherwise herein expressly provided or unless the context otherwise requires:
(i) the terms and expressions used herein shall have the same meanings as
corresponding terms and expressions used in the Indenture; and (ii) the words
"herein," "hereof" and "hereby" and other words of similar import used in this
Supplemental Indenture refer to this Supplemental Indenture as a whole and not
to any particular section hereof.







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         2.       Consolidated Net Income.  The definition of Consolidated Net
Income shall read as follows; with the change indicated by underline:


                  "Consolidated Net Income" means, with respect to the Company
         and its Restricted Subsidiaries, for any period, the aggregate of the
         net income (or loss) of the Company and its Restricted Subsidiaries for
         such period, determined on a consolidated basis in accordance with
         GAAP; provided that there shall be excluded from such net income (to
         the extent otherwise included therein) (a) the net income of any Person
         in which the Company or any Restricted Subsidiary has an interest
         (which interest does not cause the net income of such other Person to
         be consolidated with the net income of the Company and its Restricted
         Subsidiaries in accordance with GAAP), except to the extent of the
         amount of dividends or distributions actually paid in such period by
         such other Person to the Company or to a Restricted Subsidiary, (b) the
         net income (but not loss) of any Restricted Subsidiary to the extent
         that the declaration or payment of dividends or similar distributions
         or transfers or loans by that Restricted Subsidiary is not at the time
         permitted by operation of the terms of its charter or any agreement,
         instrument, judgment, decree, order, statute, rule or governmental
         regulation applicable to such Restricted Subsidiary, or is otherwise
         restricted or prohibited in each case determined in accordance with
         GAAP, (c) the net income (or loss) of any Person acquired in a
         pooling-of-interests transaction for any period prior to the date of
         such transaction, (d) any extraordinary gains or losses, including
         gains or losses attributable to Asset Dispositions not in the ordinary
         course of business, and (e) the cumulative effect of a change in
         accounting principle and any gains or losses attributable to writeups
         or writedowns of assets, and (f) any reduction for exploratory and
         abandonment costs and geological and geophysical costs, net of the
         income tax effect reflecting the income tax rate in the Company's
         financial statements for the applicable period.


         3.       Governing Law. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED 
BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK BUT
WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT
THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED
THEREBY.


         4.       Counterparts. The parties may sign any number of copies of 
this Supplemental Indenture. Each signed copy shall be an original, but all of 
them together represent the same agreement.


         5.       Effect of Headings.  The Section headings herein are for 
convenience only and shall not effect the construction thereof.


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         IN WITNESS WHEREOF, the parties hereto have caused this Supplemental 
Indenture to be duly executed as of the date first above written.


                                     HS RESOURCES, INC.



                                     By:
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                                        Name:  James E. Duffy
                                        Title: Chief Financial Officer


                                     HARRIS TRUST AND SAVINGS BANK, as Trustee



                                     By:
                                        -----------------------------------
                                        Name:  Daniel G. Donovan
                                        Title: Assistant Vice President


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